Diagnosis of Brain Tumors

Your doctor will ask about your symptoms, and medical and family history. A thorough neurological exam will also be done. This will include testing for muscle strength, coordination, reflexes, response to stimuli, your senses, thought processes, and alertness. The doctor may also look into your eyes to check for signs of brain swelling.

Diagnosis of a Brain Tumor

If changes in the brain are suspected because of symptoms, imaging tests may be done to look for abnormalities. Image tests can show the presence, size, and location of tumor. Options include:

Tumor Characteristics

Other tests will help determine specific information about the tumor which will be important to make a prognosis and treatment plan. Tests may include:

Blood, urine, and tissue tests—May be used to detect tumor markers, specific proteins that are elevated in the presence of cancer. Blood and tissue tests can be used to look for chromosome changes or inherited disorders associated with certain types of brain tumors.

Lumbar puncture
—A needle is used to collect a sample of cerebrospinal fluid that surrounds and protects the brain and spinal cord. The test can determine if cancer cells are present in the fluid.

A biopsy is the removal of a small piece of suspicious tissue for examination under a microscope. Biopsies can also help determine if the tumor may have a higher rate of metastasis, meaning they are more likely to spread elsewhere in the brain. In some cases, the location of the tumor makes it difficult or impossible to get a biopsy. Imaging tests may be able to determine enough information so that a biopsy is not needed.

Biopsy methods include:

Stereotactic biopsy—Use of a computer-assisted CT or MRI scan to specifically locate the tumor for sampling. A needle is used to remove the tissue. It is generally done with high-risk tumors that may be inoperable. Access to the tumor is through a small hole in the skull.

Open craniotomy—During a craniotomy, several tissue samples are assessed for cancer at the time of surgery. A hole in the skull allows for access to the tumor.

Staging of a Brain Tumor

Staging is a way to classify malignant primary brain tumors. It is one of many factors that help determine prognosis and treatment plan.

Tumor and Patient Characteristics

Tumor characteristics that are needed include:

Type

Location

Size

Grade—tumor growth potential

How far the tumor has spread

Possibility of surgical removal

Patient characteristics include:

Age

Level of function with the tumor

Overall health

The two most important factors that predict how well someone may do are the patient’s age and functional status. As a rule, younger patients do better, as do those who have very few symptoms associated with the tumor. Age and functional status are always considered when planning treatment.

Grading

Tumors are graded according to numerous features. All cancers are graded to identify the most promising treatment and to assess outcomes. The preferred grading system is by the World Health Organization (WHO). The tumor grades help predict the rate of tumor growth, its ability to spread, and its prognosis.

Grade I (low-grade)—Slow growing cells that rarely move into nearby tissue. They have the best chance for cure if they can be surgically removed.

Grade II—Have the potential to spread into nearby tissue. Some may turn into a higher grade tumor. These may also recur after treatment.

Grade III —Appear different than normal cells under a microscope and are likely to spread into nearby tissue. They grow faster than lower grade tumors.

Grade IV (high-grade)—Appear different than normal cells under a microscope and are quick to spread. Grade IV tumors are not cureable.

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.